Interesting post at OCLC Research about the most important categories for a bibliographic database: in short, fewer than you would think.
Those “outliers” can be categorized according to three general purposes:
- Provenance and Identity: identifiers (e.g. ISBN, OCLC, etc.) and cataloging source (040)
- Elements useful for discovery: title statement (245), personal names (100, 700) and subject (650)
- Elements useful for understanding and evaluation: publication statement (260), physical description (300), and notes (500)
That’s it. In a nutshell you have the very core of bibliographic description as defined by librarians over the last century or so.